Pipe joint



a. T. GREGG Jan. 3, 1950 PIPE JOINT Filed May 24; 1947 INVENTOR. 8%

HTTOP/KEY Patented Jan. 3, 1950 UNITED STATES PATENT oFFicE 9. Claims.

This invention has for its general object to provide an improved form ofconnection for use in hydraulic brake servicing equipment, andparticularly for effecting a fiuidtight connection between a serviceunit fluid discharge line or hose, and the-'filling'opening in a body,such as the master cylinder body, through which fluid is taken into thebrake system.

Particularly the invention aims to provide a plug-type connectionreceivable within the filling opening, and capable of simplemanipulation to assure a fluidtight seal between the wall of the openingand the fillin line.- Generally contemplated is a fitting comprising. arubber plug through which a tubular filling stem extends, and adjustablemeans forradially expanding the plu within the receiving opening" toefi'ectfiuidtight seals against both the. wall of the opening and thefilling stem.

In its more specific aspects the invention contemplates a sealingconnection in the form of a rubber plug receiving a threaded fillin stemcarrying at the outside of the plug a nut adjustable to produceaxialcompression and; therefore radial'expansion of the plug. Preferablythe tightening force of'thenuti acts to, axially com.- press the plugbetween a pair of, washers, the inner end of which is vulcanized; to theplug. In order to adapt the filling stem for use with different sizeplugs, the inner end" ofjthe stem may carry a nut removable forreplacement, of the plugs. As will appear, a specific feature is theaccommodation of the inner Fig. 2 isan enlarged CIOSSf'SGGfiOI'ISJ. viewof; the

fitting.

In the drawings, the fitting; generally indicated at In, is showntobecarriedthertubular stem l I attached at l2 tohQseISJthrQugh. whichfluids such as air,,cleansing; liquid. and hydraulic brake liquid, are,dispensed. from appropriate service equipment. not; shown.

The fluids. are. charged into a suitable; location; in. the hydraulic:

brake system, such as the master cylinder body.- l.4. containing thenormally. plugged, threaded opening IS.

The fitting I0. comprisesa rubber plug I'lihaving an external diametercorresponding closely.-

to. the diameter of, opening. IS, the plug. being carried by stem l I.in a. manner permitting; its replacement by different diameter plugs toadapt the single fitting for reception within the varying size openingsE5 of different hydraulic brake systems. The tubular stem- H isexternally threaded at l6! and extends: through an axialopening or borell of thestem carries in the plug. The inner end a nut lB having areduced diameter portion l9. received within the plugcounterbore Zll-andengageable against shoulder 21.

As willappear, nut 18 exerts against theplug an axial pressure which isapplied to a metallicwasher 22 preferably integrated, as byvulcanization, with the plug. As illustrated in Fig; 2,

washer 22 may be imbedded in theplug, and

with nut 24 loosened sufiicientl'y to permit as-- sumption by the plugof its normal diameter. Positioning of the plug within the opening isdetermined by engagement of the rubber flange 26 with the face of bodyNut 24 then is tightened against washer 25, causing nut. 18 to be pulledagainst the, plug, thus subjecting it to axial compression to a degreeresulting in radial expansion, of i the plug into fiuidtight engagementwithv the body [4, the fluid seal being aided by expansion of the rubberat the inside of opening [5, and. the overhang of flange 26 at theoutside.

seal is also created between stem H and the plug body by reason ofconstructive displacement against the stem. ofv the, rubber. as, it is.axially compressed, and particularly by reason nut l8 being pressed andmaintained, in seal-ing engagement.

of the reduced portionv I9 of against the internal plug shoulder 2|.

A sealalso is maintained to prevent fiuid.leak-- age from the containerbetween the stem and. the threads of theinner nut that only thecounterbore. threaded, so that beyond. the; an annular. shoulderengageable against; the. end

l4' about its opening l8. It will be-noted 28; of, the nut, is; threadsis formed;

tem, comprising a rubber plug receivable within.

said opening, a threaded stem for connection with a hose to pass stemextending axially within andiprojecting, metallic washers the inner andouter ends" of said inner washer being embeddedwith 7 a nut on said stemadapted to be tightened against from the outside of the plug, about thestem at the plug, in said plug and vulcanized therein, and

said outer washer to axially compress and consequently radially'expandthe plug within said opening. Y

2. A fitting for reception within an opening in a fluid receiving bodyof a hydraulic brake system, comprising a rubber plug receivable withinsaid opening, a threaded stem for connection with a hose to pass fluidinto said body, said stem extending axially within and projecting fromthe outside of the plug, metallic washers about the stem at the innerand outer ends of the plug, a nut threaded on the inner end of thestem'and having a reduced portion fitting within a counterbore in saidplug, and a second nut on the outer end of said stem adapted to betightened against said outer washer to axially compress and consequentlyradially expand the plug against the walls of said opening and againstthe stem and the outer surface of said reduced portion of the inner nut.7 V

3. A fitting for reception within an opening in a fluid receiving bodyof a hydraulic brake system, comprising a rubber plug receivable withinsaid opening, a threaded stem for connection with a hose and receivedwithin an opening extending axially'through the plug, a nut threaded onthe inner end of the stem and having a reduced portion fitting within acounterbore in said plug, the enlarged portion of the nut presenting asubstantially transverse annular shoulder to bear against the inner endof said plug and the reduced portion of the nut presenting a shoulder tobear against a mating shoulder at the end of the counterbore, a secondnut threaded on said stem at the outside of the plug and adapted to betightened against the plug to subject it to axial compression betweenthe nuts and radial expansion within said opening, said axialcompression causing said inner nut shoulders to tightly engage the plugand thereby maintain a double fluid seal. 7

4. A fitting for reception within an opening in a fluid receiving bodyof a hydraulic brake system, comprising a rubber plug receivable withinsaid opening, a threaded stem for connection with a hose and receivedwithin an opening extending axially through the plug,

inner and outer ends of the plug, a nut threaded on the inner end of thestem to exert pressure against the inner washer, and a second nutthreaded on the stem at the outside of the plug A 'fittingfor receptionwithin an opening in" a pair of metallic washers surrounding the stemand vulcanized to the against the outer washer to subject the plug toaxial compression and radial expansion and to fluid into said body, said"bring the inner nut into fluid tight engagement with an internal plugshoulder at the end of said counterbore.

' '6, Afitting for reception within an opening in a fluid receiving bodyof a hydraulic brake system,

comprising a rubber plug receivable within a threaded stem forconnection fluid into said body, said said opening, with a hose' to passstem iextending axially' within and projecting from the outside of: theplug, metallic washers about the stem at the inner and outer ends of theplug, a nut on said stem at the outside of the plug and adapted to betightened against said outer washer to axially compress and consequentlyradially expand; the plug within said opening, and a rubber-flange onthe'outer end of'said plug engageable with the outer face of the bodyabout saidopening, to form a fluid seal in response to tightening ofsaid nut.

7. A fitting for reception within an opening in a fluid receiving bodyof a-hydraulicbrake system comprising a rubber-plug receivable withinsaid opening, a-threaded stem for-connection with a'hose and receivedwithin an opening .extending axially through the plug, a pair ofmetallic washers surrounding the. stem at the inner and outer ends ofthe plug, anut on the inner end. of said steml and projecting throughthe inner washer within a 'counterbore inrthe plug, a second nutthreaded on cthestem at the outside of the plug andivadapted tobetightened against the'outer washerlto. subject rtheoplug to axialcompression andir'adialexpansion and to bring the'inne'r' nut into'fluid'tight engagement with an internal plug shoulder at the end of saidcounterbore, and a rubber flange on the outer end of said plugengageable with theoouter face of the body about sai opening to form afluid seal in response to tightening of said second nut.

8. A fitting for reception within an opening in a fluid receiving bodyof a hydraulic brake system, comprising a rubber plug receivable withinsaid opening; a threaded stem for connection with a hose and receivedwithin an opening extending axially through the plug, a nut threaded ontheinner end of the stem and bearing against the plug, and a second nutthreaded on said stem at the outside of the plug and adapted to betightened against the plug to subject it to axial compression betweenthe nuts and radial expansion within said opening, tioned nut having ashoulder bearing against the stem to form a tight seal preventing'fiuidlealgage through the engaged stem and nut threads.

9. A fitting for reception with an openifig in a fluid receiving body ofa hydraulic brake system, comprisinga" rubber'plu'g receivable withsaid' opening, a threaded -stemior connection with a hose and receivedwithin a'n'opening" extending axially throu gli th'plug, a pair ofmetalthe first men- 7 end of said stem and projecting through the innerwasher within a counterbore in the plug, and a second nut threaded onthe stem at the outside of the plug and adapted to be tightened againstthe outer washer to subject the plug to axial compression and radialexpansion and to bring the inner nut into fluid tight engagement with aninternal plug shoulder at the end of said counterbore, the firstmentioned nut having a shoulder bearing against the stem to form a tightseal preventing fluid leakage through the engaged stem and nut threads.

GEORGE T. GRIGG.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Great Britain Aug. 31, 1939

